Urban Water Management
Sustainable management of urban water has been
necessitated to ensure urban sustainability. Growing population and
aging infrastructure are creating challenges for efficient water
management in cities. Groundwater decline is major problem across the
cities relying on groundwater as a source of drinking water. Higher rate
of abstraction of groundwater than its replenishment causes water table
to decline. UN statistics reveals two people being added to the urban
population every second, and 27% of the urban population are lacking
access to piped water at home.
Declining levels of groundwater have been
assessed in cities such as Barcelona, Houston, Los Angeles, Mexico City,
New York, Rome, many large cities in China, Libya, India and Pakistan
and Middle East and Central Asian regions in a study using global
hydro-logical model PCR-GLOBWB. Dhaka, capital city of Bangladesh, faces
groundwater depletion problems as 84% of present municipal water comes
from groundwater. Groundwater levels in 54 percent of the wells in India
have been found to be decreasing and 16 percent are declining by more
than one meter per year. India experienced 10-25 mm groundwater decline
between 2002 and 2016 and 200,000 people are being severely affected by
lack of access to safe drinking water.
A positive effect of urbanisation on groundwater
includes increases in recharge by water-mains leakage, waste water
seepage, storm-water soakways and excess garden irrigation. However,
contamination from in-situ sanitation, sewer leakage, industrial
chemical pollution and disposal of liquid effluents and solid wastes are
pitfalls of urbanisation.
Management of water supply infrastructure is
challenging and expensive. Water supply pipes are mostly underground and
monitoring is arduous task. The leakage statistics of average UK home
is 133 litres per day. Huge proportion of purified water could be lost
because of aging and leaky pipes, broken water mains and faulty meters.
Increasing water demand, higher rate of water
abstraction and rapid urbanisation might induce effects such as induced
seepage of contaminated water, land subsidence and coastal saline
intrusion. Government initiatives will be less effective if vacuum
exists for responsibility and accountability of urban water management.
Integrated approach with wider participation of stakeholders, public
and private agencies will be more effective in managing urban water.